


Ahriman

by xBreeButterflyx



Category: Shadowhunters (TV), The Mortal Instruments Series - Cassandra Clare, The Shadowhunter Chronicles - Cassandra Clare
Genre: Apocalypse, BAMF Alec Lightwood, Cannibalism, Chaos, Dark Alec Lightwood, Dark Magic, Hearing Voices, Horror, Implied/Referenced Suicide, M/M, Magical Artifacts, Murder, Possession, Psychological Horror, Resurrection, Soft Husbands, Supportive Isabelle Lightwood, Undead, Vampire Simon Lewis, Warlock Magnus Bane
Language: English
Status: Completed
Published: 2019-10-21
Updated: 2019-10-31
Packaged: 2020-12-27 13:49:04
Rating: Mature
Warnings: Graphic Depictions Of Violence
Chapters: 3
Words: 8,893
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21119825
Author URL: https://archiveofourown.org/users/xBreeButterflyx/pseuds/xBreeButterflyx
Summary: When Alec gets possessed by an evil entity, it only wants one thing: death, chaos, and destruction. Can Magnus and his siblings put a stop to it or will it's power prove to be too strong to control?





	1. Possessed

**Author's Note:**

> Inspired in part by sleep deprivation, Enchantress from DC, and Dead As Fuck by Motionless in White. Hope it's worth the read.

"I can't believe this is your idea of romance," Magnus huffed as he nearly tripped over a rock.

Alec rolled his eyes at his husband's umpteenth complaint of the evening, opting to ignore it in favor of inspecting the map in his hands for the next direction they needed to go. He was much more equipt to read a map than Magnus was. Magnus relied heavily on his GPS and portals to get him around, insisting that was all he'd ever need anyways. Neither of which would be very effective navigational methods for this trip. Alec had been a little smug when he'd held up the map when Magnus had attempted to use their lack of navigation as an excuse to escape coming down here.

It was Alec's turn to choose what they did for date night. The inner nerd in him decided that this was the perfect time to make an appearance. He'd been reading up on an ancient tomb in the depths of some Persian ruins as of late, and had been utterly fascinated by the way it had been described within the book. Alec was a huge history buff, and would often borrow informative books from the Institute's vast library to read whenever he had free time. Which was usually only right before bed.

Alec had thought that once they actually got down here, Magnus would start to enjoy the experience. But they were an hour in and he was still moaning and groaning about it. Alec sighed, and decided it was high time he pull the plug. Date night was supposed to be something they could both enjoy and if Magnus wasn't having fun, he couldn't really enjoy it either.

He halted to a stop and turned around in favor of cupping Magnus' cheek. The warlock nuzzled into the touch, much to Alec's delight. "Are you ready to go now?"

Magnus sighed. "I'm fine. If you want to keep going, I suppose we can," he smiled forcefully.

Alec shook his head, shoving the map haphazardly into his backpack. "I can just come back with Max later. I'm sure he'd love something like this. Do you want to go to dinner instead?" He asked.

His husband nodded and the smile he graced him with was far more genuine, relief flooding his body at finally being able to escape this claustrophobic, earthly prison of hell. He stepped a good few yards away from the artifacts littering the floors and summoned a portal into existence.

Just as he was about to head over to the portal, a sharp glint caught his eye. He turned his head and spotted an artifact wedged between the crevices of the walls of the tomb. It was one of the most beautiful things he'd ever seen. It was a tiny crystalline figurine in the shape of a crescent moon, with a base the shape of a star. He reached out and carefully wedged the figurine out from between the walls with the tips of his fingers, grinning victoriously when it dropped into the palms of his hands. It was even smaller than his hand, and weighed no more than a pound.

He looked up when he heard his husband clear his throat expectantly. Magnus stood with his arms still open wide, holding the portal open for him to step through. Alec carefully pocketed the artifact in one of the side pockets of his backpack. Perhaps he'd gift it to Magnus later.

They ended up having a romantic dinner under the starlight in Rome. Once they arrived home, Alec decided that the figurine in his bag was far too precious and beautiful for him to keep for himself. When he gifted it to Magnus, his heart fluttered in his chest at the way his eyes lit up at the gesture. The warlock set it up carefully on the mantle in the living room, and no more was said about it. They made love to the faint sounds of the roaring city below the loft, and fell soundly asleep in each other's arms. When they woke next, it was only a few hours later, and to the sound of a loud crash from the other side of their home.

They bolted out of bed and down the hallway to be greeted by the culprit, Chairman Meow, pawing at a pile of shattered glass on the floor beneath the mantel. The cat meowed pitifully at the two of them and they both sighed. Magnus plucked his cat up and reprimanded him for climbing up onto the mantel as Alec swept the mess into the dustpan with a broom. It was disappointing, to see something that had once been so beautiful reduced to nothing but broken pieces on a floor, but he ignored it and dutifully swept it all away.

Alec's eyebrows furrowed as heard what sounded like a whisper brush against his ear, far too quiet to sound out the words. The whisper was accompanied by a shiver of arctic-like air shocking his nerves. He wrapped his arms around himself, and would have probably questioned it further, had the Chairman not chosen that moment to spring out of Magnus' arms and attempt to knock the dustpan out of Alec's hands. The shadowhunter shooed the cat and went off to dispose of the glass. He thought no more of the whisper and the chill as they went back to bed. He simply brushed it off to his sleep-deprived mind playing little tricks on him.

That was, until the voices began.

He told no one about the voices. They tormented him daily for nearly a week, but he kept that to himself. If he told anyone about it, he knew they'd look at him differently; that they'd think he was a total nutcase. He didn't work this hard for this long to let his own mind ruin everything he'd ever accomplished. It would be a cold day in hell...

_'Her voice is so annoying. I should just rip her vocal chords right out of her throat.'_

_'I wonder if the entrails of a daylighter taste any better than the entrails of the average vampire?'_

_'Magnus looks so beautiful writhing beneath me. He'd probably look even better with my hands wrapped around his throat, gasping for air.'_

_'He smells delightful. His liver is probably full of flavor.'_

Alec screamed as the voices got louder and louder, darker and darker. He gripped his own hair tightly, needing something to hold onto as his sanity was ripped clean away from him. The thoughts only got more and more twisted, until he was nothing more than a panting, sobbing mess on the floor of his office.

The door of his office flew open as Isabelle burst into the room, eyes wide and alarmed as she fixiated on her brother collapsed on the floor. She rushed over to him and gathered his shaking form into her arms, consoling him the best she could. Her soft, soothing words combated the darkness within his mind until eventually the voices that had been yelling at him before were nothing more than a frightening little whisper. Soon enough, felt himself begin to drift away in her arms.

He should feel ashamed to be letting his little sister see him like this at work, of all places. But he couldn't bring himself to care too much at the moment. Not when the relief flooding his system was so great. He was just so grateful that the voices were gone. He wanted to enjoy that for as long as he could. Isabelle continued to whisper those gentle, soothing words to him, even long after he'd fallen asleep.

Awhile later, when he woke up on the couch in the loft, he started to feel the horror dawn on him of what had happened. Isabelle must've called Magnus to portal him home. He felt mortified. If Magnus and Isabelle now knew about it, it was only a matter of time before everyone else did too. Only a matter of time before the Clave found out about his instability. Only a matter of time before he lost everything he'd ever worked for.

"Alexander?"

Magnus was standing in front of him, eyes soft and concerned as they bore into his own. Alec reached up and laced their fingers together, pulling his husband down into his embrace as he did so. Magnus went willingly, and even hummed as Alec buried his face in his hair. The warlock slid elegantly into his lap and curled around him. They sat like that for a few moments, basking in their little moment of comfortable solitude while they could.

Alec pulled back eventually, voice small and frightened as he spoke. "Magnus... There's something seriously wrong with me. I think I need help," he whispered.

Magnus frowned. He cupped his husband's face in his hands and pressed their foreheads together, stroking his thumbs across his cheekbones affectionately. "What's going on, darling?"

The hunter opened his mouth to reply, but when he did no words came out. He tried again, and this time a sharp pain wracked through his torso, starting in the middle of his chest and spreading outwards until it was consuming his entire body. He wanted to scream, cry, something, but he couldn't push any sound out past his lips. He clawed desperately at his chest, trying to will the agony away to no avail.

It felt like there was something -_or someone_\- trying to claw its way out of the very depths of his soul. It ripped its way past his organs and bones as if they were nothing, merely obstacles in its path. He began to convulse violently in his seat, his eyes rolling back as he tried, and failed, to fight back against whatever was tearing him apart. The last thing he was aware of was his mouth foaming so much it spilled down his chin, and the horrified screams of his husband in his lap.

×××

Magnus clasped his husband's hand tightly as he stared down at him, silently willing him to finally wake up. He'd straight up refused to leave the infirmary for anything, even when Isabelle had offered to take him out to lunch at Takis on her. He understood that she meant well, but he was aggravated. People kept trying to pull him away from Alec left and right, and that was just not happening.

When Alec had begun to convulse on the couch, Magnus took the signs for what they were. A demonic possession in progress. He put a stop to it before the demon could get its claws too far embedded into his husband, but he knew that would only be a temporary fix to the problem. He called Catarina to help him banish the demon inside of Alec, and had been shocked to discover that not one of the demonic banishing rituals they performed were effective. Catarina informed him that what they were dealing with had to be something other than a demon. She ordered him to keep Alec in check while she and a few of her other warlock friends got to the bottom of what was happening. Magnus was still awaiting her call.

Magnus' breath caught in his throat when Alec began to stir, finally beginning to slowly regain consciousness after nearly two whole days. Alec blinked harshly against the light of the room, squinting up at his husband from where he lay on the bed.

"Magnus...?" He mumbled.

"I'm right here, angel," he assured, pressing his fingers more insistently into the side of his head he was currently running his fingers through.

Magnus immediately informed him of what he and Catarina had discovered, doing his best to put a clamp on his emotions as he did so. It wasn't an easy thing to be hit with; finding out you're being possessed by a demon/not demon. Alec was, shocked, to say the least. But eventually, when he had finally gathered his bearings, he shot out of bed, much to Magnus' shock and objection. He pleaded with the other man to lay back down and rest; worried about his health and the tendency he had for straining it. Alec retrieved his keys from his office and allowed Magnus to follow him down to the cells, confusion sweeping over him as he watched his husband approach the largest one the Institute had. He turned to face Magnus expectantly, thrusting the keys into his palms.

"Lock me in here."

Magnus began to sputter. "You want me to lock you in a _cell_? And for what, exactly?"

Alec moved in close, cupping Magnus' face in his hands and pressing their foreheads against one another. He tentatively moved in for a kiss, which Magnus couldn't help but to reciprocate. This was how it had always been; how it always would be. Magnus had a certain helplessness when it came to Alexander that he'd never really had with anyone else. He could never deny him anything.

"Magnus, baby... This, _thing_, inside of me. It's very... _Dark_. And powerful. I don't want to hurt anyone when it takes control. And it will take control. It's only a matter of time," Alec whispered against his lips, eyes shut tight, almost as if he were bracing for an impact of some sort.

Probably one he expected from Magnus.

"Alexander, _I'm_ powerful, in case you-"

Alec cut him off with a sharp groan, shaking his head harshly at Magnus' words. "You are. But I've felt your magic before; and it is not nearly as strong as this. _Please_. I need you to find some warlocks to join you in putting some heavy protection spells on the cell. It's the only way to contain it. At least, until we figure out how to stop it."

So Magnus did what he was asked to. Despite how much he wanted to fight his husband on it, to ensure him that he could protect him just fine on his own and outside of a cell, he respected Alec's wishes and called upon four other warlocks to assist him in containing Alec inside of the cell.

It only took a few hours for the show to begin. When Alec looked up at him from beneath his dark, heavy lashes through the window, and Magnus saw that the color of his eyes had shifted, his breath caught in his throat. They were the color of blood, feral and ready to kill. Alec grinned manically at the warlocks, rising up from his seat on the ground and surveying his surroundings.

"Locking me up? That's not very nice," he taunted, creeping slowly up to the window as he inspected his captors.

Awhile later Alec, realizing that no amount of words were going to convince them to release him, grew furious. He summounded a dark kind of matter from the air and into his palms and began launching attack after attack at the door of the room. It was of no use; he was locked in there tight and there was nothing he could do about it. Once that failed, his eyes narrowed in on the tear tracks on Magnus' face, and his lips upturned into a mischievous grin.

Magnus gulped, knowing damn well whatever happened next was not going to be pleasant. Alec was bent over on his knee, unwinding his shoelaces from his sneakers and fastening them together to create a makeshift noose. Magnus watched on, confusion steadily clearing as Alec tightened the noose around his neck and tied it around the ceiling fan above.

The minute Alec kicked the chair back and started to dangle in the air, laughing silently at the way Magnus' resolve broke in two, was the same minute Magnus dropped the protection spell and raced over to the cell, throwing open the door without another moment's hesitation.

It's also that very same minute that Alec summoned more of that dark matter into the palm of his hands, and before anyone had any time to react, blows the cell into millions of pieces. Magnus goes flying back against the wall of the cell, and is knocked clean out by the impact of his skull colliding with the concrete. The last thing he sees is Alec's laceless shoes, walking towards the exit as the sound of the Institute's alarms ring sharp and loud in his ears.

* * *


	2. Apocalypse

"Magnus? Magnus!"

The light of the room shone harsh and bright against his eyes as he blinked them open. He gasped for breath, anxiety hitting him the instant he awoke. Knelt in front of him was Isabelle, with Jace and Simon standing a little ways away, assisting the other warlocks; checking for survivors. The cell block was reduced to nothing but rubble. Luckily, the support beams above remained intact, otherwise the entire Institute would've come crashing down on them all. They probably wouldn't have survived that.

Isabelle breathed a sigh of relief when he opened his eyes, and began to immediately assess him for injuries. He swatted her away, trying to stumble his way onto his feet but to no avail.

"Alec... Alexander... He-"

"He's gone," Jace said, he and Simon now finished with their inspections of the other warlocks. There was only one other survivor. A few other shadowhunters were leading him up to the infirmary for treatment, the warlock far too weak to heal himself.

Magnus tried to swallow down the red hot anger that threatened to spill. "He's_ gone_? You all just let him walk through the front door? Just like that?"

Jace sneered, insulted. "At least we didnt open the cell and let him out."

Magnus flinched.

Simon piped up from where he was stood behind Jace, waving his hands frantically. "Dude you should have seen it! It was incredible! Alec just _walked out _of here, through the ops center and out the doors. He had like, half the Institute trying to kill him and he was just flicking them across the room like they were ants! He didn't even have to touch them," the vampire rambled, eyes wide and amazed as he finished his little tirad.

Magnus' jaw dropped. "They were trying to _kill him_?" He hissed.

Isabelle nodded, eyes narrowed in anger at the incident. "Word got back to the Clave that he was possessed and they put a kill order on him if he were to escape. To prevent further carnage."

The warlock used the remnants of his energy to heal himself just enough to rise to his feet, and when he did he stumbled towards the exit of the cell blocks. The other three quickly followed, Isabelle staying close to ensure he didn't collapse into the ground. Once they were up in the ops center, Magnus went for one of their phones, dialing Catarina's number by memory and waiting impatiently for her to pick up the phone. If she didn't have an answer for him this time, he might just scream.

"Catarina Loss speaking."

"Cat. It's Magnus. Please tell me you have something," he urged.

"Yes, I do. I think I know exactly who is possessing your husband. I've been working on an entrapment to recapture his soul for the last hour or so but it's not finished yet. Just one second," she trailed off.

The call disconnected and about a minute later Catarina strode through the front doors of the Institute, eyes wide and mouth gaping at the wreckage inside. She carefully stepped over a few corpses of the fallen shadowhunters to approach Magnus and his friends, sighing softly. Surprisingly enough, she didn't look shocked to see what had happened inside the Institute; only sad.

"Alec's gone. I couldn't contain him, Cat," he said miserably.

She nodded. "I know. After I found out who was possessing him, I knew there was no containing him."

Isabelle placed a hand on her hip, lips pursed, her impatience evident. "Well? _Who_ is possessing my brother?"

Catarina addressed Magnus as she explained. "When you told me this started right after you visited a Persian tomb, I went down there to investigate. After seeing some of the markings on the walls, and the artifacts, it all made sense. The reason why our demonic banishments didn't work was because we're not dealing with a demon at all. Magnus... We're dealing with a _god_," she stressed.

The reactions could've almost been comical save for the gravity of the situation. Nearly all of them were stunned into silence, save for Simon, who was sputtering and waving his hands about towards Catarina.

"A-a _god_? But I thought God was supposed to be good? This thing is wreaking nothing but havoc!" Simon cried indignantly.

Catarina shook her head. "The god you're thinking of is. Not all gods are good. Some of them are evil. The one we're dealing with is Ahriman: god of evil and darkness; according to Persian mythology. He was believed by the Persians to be the force behind anger, greed, envy, and negativity in general. He brought them chaos, disease, and death. And if we don't stop him, he's going to plague New York with it as well."

At that moment, the sounds of blaring sirens and horns began to echoe from the outside. It wasn't like the occasional emergency responder to fly by the church every now and again, no. This was several sirens flying by all at once. The group glanced at one another, silently hoping that it wasn't what they thought it was. They raced over to the doors and flew down the steps of the Institute, and what they were greeted with on the outside was chaotic.

The sky had darkened significantly above, casting little light over the city. There were several emergency responders racing towards the inner city, sirens blaring urgently as they surpassed all of the cars on the streets. There were about a few dozen mundanes running away from the direction the emergency responders were heading, eyes open wide with panic and terror as they fled for their lives. Some of them were so desperate to get away from whatever it was they were running from that they were using the streets as passage, and the unlucky few got ran over by the fleeing cars.

"I think we're already too late," Jace murmured, swallowing hard against the thought of Clary being somewhere amongst that crowd, frightened and unsafe. He had to get to her. "I-I have to go. Clary..." He trailed off, arming himself with his blade and taking off in the direction of her art studio.

"Jace, wait! We need your help-" Isabelle called after him.

But it was of no use. Jace was already gone. It was only down to the four of them now. Magnus turned his attention back to Catarina, who was staring at the scene in front of them with unmasked horror. As a medical professional, all she wanted to do was help. But there was only one of her, and millions of them. There was but one thing she could do to save them.

"Cat, how fast can you have that entrapment finished?" He asked.

She blinked back the tears that threatened to spill, pulling herself together with a deep, calming breath. "I don't know. Another hour at the least. I'll work as fast as I can," she replied.

"Okay, we'll control the situation as best we can until it's finished," Isabelle declared, readying her whip and climbing the stairs the rest of the way to enter the madness below.

And then there were three. Catarina disappeared into a portal to finish the entrapment, while Magnus, Isabelle, and Simon pushed their way through all of the hysteria to the inner wreckage of the city. It took nearly half an hour to make it, being knocked around left and right by the mundanes, unable to portal as Magnus saved up his energy for the battle ahead, but they finally found the source of the carnage. And it was absolutely horrifying.

Nearly an entire block of the city was littered with corpses, men, women, and children alike, all of them beyond recognition. Magnus would even question if they were human if it weren't for the mangled clothes on their bodies. Blood and gore was spilled all across the pavement. The sight and the stench combined nearly had him hurling all over his boots.

"Oh, Raziel..." Isabelle whispered.

"He did all of this in less than an hour?!" Simon choked, fists clenched angrily at his sides at the tragic sight before them.

Magnus only nodded. His eyes lingered on one of the smaller bodies, its shoes no bigger than the size of his hand. He wanted nothing more than to tear Ahriman apart limb from limb for what he's done. But Ahriman had no limbs, only a soul they could entrap inside of whatever Catarina was piecing together. Magnus swore to himself he'd figure out a way to destroy Ahriman's soul once this was all over. He didn't care how long it took.

"Where is he?" Isabelle wondered aloud, stepping over the bodies to search for her brother.

"I'm gonna take a shot in the dark here and say that that's him," Simon replied, pointing in the direction of one of the cars turned over down the street.

It was Alexander, alright. He was dressed differently, but it was him. He was wearing tight leather pants, black combat boots, and a black opened trenchcoat with an upturned collar. Magnus hated to admit it, but that god had more fashion sense than his own husband did. Perhaps he could convince him to keep the outfit once this was all over and done with. Because Alexander was going to come home safe and sound with him. That was not even a question.

Magnus nearly fainted when he saw what Ahriman was doing; wearing the face of the man he loved. He was bent over the mangled corpse of a mundane woman, tearing into her throat with his teeth and devouring her esophagus raw. There was blood and guts already soaking into his clothes, covering his face. Ahriman didn't seem to mind the mess as he continued to tear into the poor woman ferociously; until he noticed the three of them approaching from the distance. He tossed the woman's body carelessly off to the side and stood to face them, wiping the gore off of his chin with his arm.

"You're just in time," he smiled gleefully, rolling back his sleeves.

Magnus raised an eyebrow. "Just in time for what, _Ahriman_?" He spat.

Alec only tilted his head. "So you know my name? All the better. I want you all to remember the name of the one would brought about your end. You all thought you'd bested me, didn't you? Trapping me in that glass for four thousand years? How fitting, that the very thing you thought had saved you only served to bring about your end."

Isabelle rolled her eyes. "By the angels, you ramble even more than Simon does."

"Hey!"

Magnus shushed them both. "What are we in time for, Ahriman?" He asked.

Rather than answering, Alec took a few steps back from them, arms spread, whispering something to himself so quietly that none of them could hear. His whispering gradually rose in octaves, his eyes rolling and limbs shaking with the energy his words were calling forth.

Magnus, Isabelle, and Simon, all had an unspoken agreement that whatever this was probably wasn't going to lead to anything good as they side-eyed one another. So Isabelle and Simon launched themselves at Alec as Magnus tried to bind him in place with his magic. He was only left stunned as his magic backfired off of Alec's body and shot itself right back at him. He managed to throw himself to the ground and out of the way just in time before he was bound by his own damn power.

Isabelle and Simon found themselves running into the car behind Alec as he levitated up and out of their reach. He climbed higher and higher as the energy he gathered from his spell grew.

"Nam tu, qui dormit in lapidibus et argilla, videte hoc dicere, surge et obedire, treck in per Mortale ostium, convenire caro et ambula semel," Alec cried out.

"Nam tu, qui dormit in lapidibus et argilla, videte hoc dicere, surge et obedire, treck in per Mortale ostium, convenire caro et ambula semel!" he was screaming now, shaking violently, the reds of his eyes replaced with solid white.

Then the energy suddenly reached its peak, and a ripple of shock waves could be felt across the cosmic plane. Isabelle and Simon probably felt nothing, but Magnus, being so intimately tapped into it through his magic, felt everything. Which meant he could also feel how off-balance Ahriman had thrown it. Not only was he bringing chaos to the physical world, but the astral world as well.

A group of shadowhunters approached from the other end of the street, halting to a stop when they set their sights on Alec. They readied their weapons, a few of the hunters with long-range weapons opening fire at him from below. Like Magnus' magic, it backfired, and went flying towards them instead. Magnus flung his hands up, stopping the arrows and bolts just in time, a few of them mere inches from piercing the nephilim's skulls. A part of him wanted to just let them die, for trying to hurt his husband, but he just couldn't stomach seeing anymore bloodshed. Not after all of this.

By the time they all looked back up after having dealt with the near misses with the bolts and arrows, Alec was gone. The group of hunters swore, taking off in a random direction to hunt him back down. Magnus lowered his hands, dread filling him at the thought of what Ahriman had just done. The world wasn't collapsing in on itself yet, nothing seemed to have changed, but he couldn't deny how inherently _wrong _the energy in the atmosphere felt. Something was set very off balance, and he had a feeling they were all going to find out what it was soon enough.

"What did he just do?" Simon asked, eyes fleeting around the block nervously.

"I don't know. Let's go find out," Magnus replied, setting off back in the direction they came from, towards the mundanes. He had a feeling that Ahriman's wrath was mostly aimed at the lot of them.

It took only a few minutes for them to get close enough to the mundanes to find out what the god had done. If Magnus had thought they were frightened before, it was nothing compared to this. They were all screaming at the tops of their lungs, throwing each other carelessly out of the way for the sake of their own self-preservation. What they were running from looked like something straight up out of a horror film.

Corpses, all in varying states of decay, were snatching up and murdering mundanes. They looked like they'd just dug themselves out of their own graves, dirt matting their hair (the ones that had it), and their clothes. The corpses were smashing their skulls, choking them out on the pavement, using whatever was at their disposal to end their lives.

"Oh my god, Magnus, I think your husband just kickstarted the fucking apocalypse!" Simon cried out, whipping out a blade to fend off the oncoming attacks from a few of the undead.

Magnus and Isabelle joined in the fight, taking down as many of the corpses as they could. For now, this was all that they could do to help. The undead were relentless, more and more replacing the ones that fell. Mundanes were dying left and right, bodies filling the streets like cars as they were slowly and steadily losing the battle. It was all up to Catarina now. If she didn't perfect that entrapment, New York was going to end up nothing but a memory.

And so was his husband.

**Notes for the Chapter:**

> "Nam tu, qui dormit in lapidibus et argilla, videte hoc dicere, surge et obedire, treck in per Mortale ostium, convenire caro et ambula semel."
> 
> Translation:
> 
> "For thou who sleeps in stone and clay, heed this call, rise up and obey, treck on through the Mortal door, assemble flesh and walk once more."


	3. Resolution

Jace slashed down another one of the undead as he fought his way towards Clary's art studio. He had been hoping to make it there before something catastrophic like this had happened. But he'd not been so fortunate. He could only hope that Clary was safe, and that none of these things had broken into her studio yet. At least, not before he could get there to protect her.

He was just turning the corner to the next block, the block with the studio on it, when one of the undead took him from the side with a surprise attack. He cried out in shock and they both went flailing into the sidewalk. He tried slashing at it from the side, but another one of them dove ontop of him. They were clawing at him, hitting him, the newest one now had its hands wrapped around his throat, choking him. 

Jace decided his best course of action for now was to forget about the blade. He dropped it in favor of kicking the first one in the ribs, sending it flying back a few feet away while he locked his knees around the sides of the one choking him, using his momentum to flip them over. He snatched his blade back up and sliced through its arms, the creature howling in pain at the dismemberment. He whipped around just in time to slice the head of the first one clean off as it came for him, having recovered from his initial attack.

He finished off the second one and continued on his path to the studio, slashing down any of the creatures that stood in his way as he went. He was running on pure adrenaline and fear now. Not fear for himself, but fear for Clary, and her fate. That fear amplified as he approached the studio, and heard a shrill shriek sound from inside. The doors were locked up tight, but two of the windows had been smashed clean through, glass scattered all around the ground below.

"Jace?"

The blonde whipped around to be faced with another approaching shadowhunter. It was none other than Luke, Clary's unofficial stepdad. He was running towards the studio from the opposite direction Jace had come from, the direction of The Hunter's Moon. He had a blade in hand, and fear and confusion in his eyes as he slashed his way through the chaos and towards the studio. It didn't take him too long to slow to a stop by Jace's side, which was a good thing, because Jace wasn't about to wait too long before storming the building.

"Jace, what's going on here? What did Alec do?" He asked.

"No time. Clary's in there with who knows how many of those things. Let's go," Jace replied, climbing the steps and promptly kicking the doors to the studio in from the outside.

The pair had their blades at the ready, creeping carefully through the darkened halls. A couple of the undead tried to blitz attack them from the shadows, but they were prepared, and took them down with ease. They made it to the double doors of the main studio in no time, which had already been broken into, evident by the splinters of wood scattered all over the floors. Luke shoved the broken doors aside and they burst into the room.

Clary was standing amidst the wreckage of several of her paintings. Two of the undead were at her feet, dead once more. She was panting, sweaty, clothes in tatters. In her hands was a sharpened wooded leg from one of the easels, coated in blood. Off to the side, they found the source of the scream Jace had heard from outside. It was one of Clary's fellow artists, a brunette woman appearing to be somewhere in her 30s. She was huddled up in a corner, holding her knees up to her chest and hyperventilating into a Takis to-go bag.

Jace's breath caught in his throat as his eyes landed on an intricate marking on Clary's neck. It was a rune. His eyes searched the rest of her skin frantically, and was stunned to see the rest of her runes etched back into her skin, almost as if they'd never disappeared in the first place. They were all in the same place they'd been before they had vanished, as if the angels had gifted them back to her.

And when Clary's eyes locked onto his, and that familiar spark of recognition and undying love lit up in her irises, he knew that her runes weren't the only thing that had been regifted to her.

The angels had forgiven her at last.

×××

Magnus, Isabelle, and Simon were beginning to grow impatient. Nearly an hour had passed since Catarina had portaled back home to finish her entrapment, and there was still no sign of her return. They were tired, all of their energy nearly spent into fighting all of these creatures off. Isabelle was the only one with enough energy to keep going, having activated her stamina and strength runes somewhere along the way. Simon and Magnus backed her up the best they could, but they were nearing the edge of complete exhaustion. Magnus felt like he would pass out at any given moment.

"We need to retreat for now; give you two some time to recover!" Isabelle ordered.

"But what about all of these people? We're the only ones that can protect them!" Simon protested.

Isabelle sliced her whip through one of the undead that Magnus hadn't noticed coming at him from his right, its head flying through the air and disappearing into the crowd. "We're of no use to the mundanes dead. Let's go," she said.

The three of them scored a fire escape down the street and Isabelle kicked the last few landings clean off to avoid any of the undead following them up. Magnus and Simon collapsed onto the roof while Isabelle did a perimeter check. She found only one of the creatures up here with them, wandering aimlessly behind some of the ventilating units. She took it down easily enough before joining them on the ground.

They sat in silence for several minutes, regaining their strength for the rest of the battle. Soon a portal opened near the ventilating units, and Catarina rushed out. Magnus breathed a sigh of relief at the tiny glass figurine she had clasped in the palm of her hands. It was nearly identical to the one Ahriman had been trapped in before. Magnus rose to his feet to greet her.

"It's done. I have several warlocks ready to bind Ahriman long enough for you to recite the spell to trap him inside. They won't be able to hold him for very long, so you need to be quick. You need to distract him long enough for them to get into position as well. If he notices any kind of setup taking place, he'll smite us all where we stand," Catarina explained.

Simon snorted. "How reassuring."

Catarina leveled him with a look. "I'm not here to reassure you. I'm here to save lives."

She reached into her jacket and pulled out a carefully folded slip of paper. She slid it into Magnus' palm. "This is the spell you'll need."

Magnus opened it and memorized the lines, engraving them in his brain for later use. He slid the paper into his own pocket and thanked Catarina with a kiss on the cheek.

"Magnus... Something's coming," Isabelle said, readying her whip and rushing off towards the fire escape.

Simon launched to his feet at the same time Magnus and Catarina summoned their magic to their hands, approaching the fire escape cautiously. Isabelle was the first one to see what was down there, and at her sigh of relief, the other three relaxed a little. Her eyes went wide a split second later, lit up in shock and delight at what she saw below.

"Clary?" She gasped.

Simon whipped his head up at the name, maneuvering his way around his girlfriend to look down the fire escape.

A few moments later, three shadowhunters launched themselves up onto the rooftop. Jace, Luke, and to everyone's surprise, Clary Fairchild. Besides her hair, she remained unchanged. Her runes were all in the same place they were before, her eyes weighed down with all of the knowledge only the shadow world could offer. Magnus grinned. The angels were capable of forgiveness afterall.

Simon and Isabelle descended upon her immediately, hugging her close and throwing about a million and one questions at her as to what had happened for her to get her runes back. Luke gently pried them off of the girl, holding up a hand to silence their ramblings.

"We can talk about Clary later. Right now we need to focus on what's going on down there," he said, gesturing to the streets below them.

Clary turned to face Magnus, expecting him to have the answers, apparently. "Yeah, what are those things? What did Alec do?"

Magnus' face turned grim. "Alec didn't do anything. There's a Persian god named Ahriman possessing his body; he's done all of this. He raised the dead from their graves to slaughter all of New York."

Catarina decided to interject. "And he will do the same to the rest of the world if we don't stop it here. Jace, can you track your parabatai for us? We need to know where to position ourselves," she asked.

Jace nodded and pulled his stele out of his jacket pocket, stepping off to the side to do the tracking. When he returned, he gave them the coordinates to a nearby airport. With that knowledge, Catarina disappeared into another portal. Assumably returning back to her group of warlocks to prep them for the battle ahead. Magnus and the rest of their group decided it was best to split into teams of two. Magnus, Isabelle, and Jace would go to the airport to capture Ahriman and Clary, Simon, and Luke would stay behind to protect the mundanes the best they could. Jace objected to being separated from Clary, but once she hugged him and reassured him that she could handle her own, he let it go.

Once the three of them arrived at the airport, they ascended the steps to the front doors. Magnus shoved one of the doors open, only to nearly trip over a mundane lying on the floor of the lobby, his clothes drenched in blood. Magnus' gut clenched painfully as he surveyed the rest of the lobby. Hundreds of bodies were scattered across the floor, not a single living soul in sight.

"I guess we won't have too hard a time getting past airport security," Jace quipped.

He snapped his mouth back shut at the matching glares Magnus and Isabelle leveled him with.

"So how are we going to distract him anyways?" Isabelle asked.

"Me," Magnus replied simply, leading the two of them through the lobby and down the halls of the building.

Isabelle stumbled over the body of one of the security guards as she struggled to keep up, Magnus moving with such a quick determination that he was a blur of movement to anyone watching on from the outside. "You?"

The warlock hummed, confirming her question. "Alec is still in there somewhere. If I can try to coax him out, then Ahriman will be distracted trying to regain total control over his body. It may only last for a few moments, but that's all I need," he explained.

The three of them finally emerged at the entrance of the airport hangar. Magnus threw the doors open as dramatically as he could with a wave of his hands, making the loudest and most eye-capturing entrance into the outside that he could. It was quite effective, as Ahriman must've sensed it as the energy in the air fluctuated. There were several planes on the hangar, but he emerged from one of the smaller ones nearby, hands shoved in his pockets as he casually strolled down the steps of the platform.

"I regret to inform you, there's no more seats available on this flight," Alec teased.

Magnus only smirked. "I think one is just about to open up."

At that, Alec laughed, eyes lit up with a sort of amusement and cocky demeanor that was not akin to his personality in the slightest. "Oh? A baby warlock and his nephilim lackeys have come to kill a four thousand year old _god_? Am I hearing that right? I don't know if you're optimistic or just plain stupid. Perhaps both," Alec replied, having finally stepped off the stairs and was now making his way across the blacktop of the hangar.

Jace huffed. "Who are you calling a la-"

"Shutup, Jace," Isabelle snapped, fed up with her adoptive brother's ego and constant need for validation.

Ahriman's cockiness would be his downfall. He knew his type all too well. The kind of entity that was so powerful they let it go to their head, they left themselves vulnerable to certain, unexpected attacks because of their firm belief that nothing could ever touch them. Magnus was about to prove him wrong. He decided that now was the time. He knew he couldn't address Alec directly, otherwise Ahriman would know what he was up to a little sooner than he was planning.

"The omamori charm from Tokyo. I still carry it with me every single day. It was the first gift anyone had given me in decades, and I cherish it more than almost anything else I own," Magnus said, voice unwavering and clear as he spoke. He needed to make sure Alec could hear every bit of what he was saying. He had to give him the strength and motivation to fight Ahriman, even if he could only manage for a few seconds. It would be more than enough to save them all.

Alec narrowed his eyes at him. "What are you talking about?"

He continued on, unfazed. "First night in Havana. Two left feet, but I couldn't care less. Was just content to be there with the one I loved most in this world. Drinking and stumbling and laughing and kissing was most of what occurred throughout that night, and what a night it was. I still remember the way my heart melted at that embarrassed, goofy little grin I was graced with when my feet were getting trampled over."

Alec was starting to fight back, Magnus could tell it. Ahriman was growing angry, fists clenched at his sides as he struggled to keep himself in check. He was breathing slowly through his nose, trying to force Alec back down into the darkness of his consciousness. But Magnus' words were the fuel to keep him going, so he continued on. This time, he decided to throw his whole entire hand down. It was all or nothing. He would address Alec more directly, and give everything he had into this one. It could end badly, with Ahriman striking them down where they stood. But it could be that last little shove Alec needed to regain a few moments of control.

"Our first night as lovers. It was messy, and imperfect, but it was more beautiful and magical than anything I had imagined up until then. Alexander, when you saw my warlock mark, you didn't flinch away like most people usually do. You embraced all of me with nothing but acceptance and love. You called me beautiful, and made love to me with everything you had, despite how nervous and inexperienced you were. Because you loved me as I love you. What we have is so much more powerful than anything this man thinks he possesses. Because our love is pure and gentle, raw and real," Magnus finished, tears welling in his eyes at the proclamation.

Alec blinked. Once, twice, and then, in a small, frightened little voice, he said-

"Magnus?"

The warlock's heart melted as he locked eyed with those same pair of bottle blues he fell head over heels with from day one. They were open wide in fear, staring at Magnus desperately, silently begging him to help him.

Suddenly, Catarina and seven other warlocks emerged from a few of the other planes, standing on the platforms as they all simultaneously casted the binding spell on Alec. Ahriman fought back then, Alec's eyes rapidly flashing back and forth between blue and those demonic red from before. The four warlocks struggled to contain him, their magic straining under Ahriman's power.

"Magnus, do it! Now!" Catarina ordered.

He quickly recalled the spell to the forefront of his mind, and brought the entrapment back into his palms. He recited the spell as fast as he could, desperately trying to finish before Ahriman inevitably regained full control over Alec's body and broke free of the binding spell. He breathed a sigh of relief when he finished just in time, Alec's body collapsing into the ground as Ahriman's spirit left him and entered the entrapment.

Magnus was about to fly over to his husband when Catarina blocked his path, discreetly snatching up the entrapment and shoving something else into his palms. He looked down and was surprised to see it was a replica of the figurine, only this one he knew was empty of a soul. He looked up at his friend with a quizzical raise of his eyebrow.

"It's why I took so long to return. You'll understand soon enough. Go to your husband. He needs you," she whispered, hurrying off to tend to the mundanes in the city with her team of warlocks.

Magnus rushed over to Alec's side, gathering him into his arms and sobbing as he threw his arms around him in return. They breathed each other in, relieved to finally be safe in each other's arms at last.

"I love you. I love you so much. You better not do that to me ever again!" Magnus cried, clutching onto his shadowhunter even harder as his emotions began to overwhelm him.

Alec snorted through his own tears. "What? Get possessed by an evil god? I'll try to make sure I leave that off the schedule next week."

Magnus pinched his side in retaliation to the snarky comment. They had just begun to pull back from each other when a group of shadowhunters stormed the hangar, weapons draw and aimed directly at where Alec was collapsed on the ground.

"Hey! Hey! Hey!" Jace and Isabelle screamed, throwing their hands up and moving to block Magnus and Alec from view of their comrades, ready to defend their brother and brother-in-law at a moment's notice.

"It's over. We recaptured Ahriman's soul in another entrapment," Jace explained, visibly relaxing as the group in front of them lowered their weapons.

One of the women amongst them spoke up. "By order of The Clave, we demand that you hand over this entrapment to us to be delivered to the Inquistor."

Magnus understood then, why Catarina had given him a replica of the entrapment. She had foreseen The Clave demanding to have possession of Ahriman's soul. The Clave could not be trusted to protect their own people, much less a dangerous, world-altering artifact. He silently produced the figurine and handed it off to Isabelle to give to the woman. When she had it in her possession, she and her companions portaled out of the hangar.

Alec made to get up from the ground, but Magnus held his husband closer to his chest, not ready to part with him quite so soon yet.

"Magnus. Those corpses might still be running rampant through the streets. We have to go wipe them out if they are," Alec insisted, gently prying his arms off of him and climbing his way back to his feet.

The warlock huffed and followed his husband and his siblings towards the exit of the hangar, ready to put an end to this nightmare once and for all. Isabelle and Jace disappeared through the doors into the building and just as Alec was about to walk through after them, he spun around on his heel and grabbed the lapels of Magnus' jacket, yanking him into a passionate, mind-numbing kiss full of knocking teeth and twists of tongue. They pulled back breathlessly after a few moments, foreheads pressed against each other as they panted together.

Alec's eyed were soft and warm as he whispered, "I love you too."

And then off they went to slaughter the rest of Ahriman's undead. It took them and the rest of the shadowhunters nearly a week of hunting to ensure that they'd gotten them all, but that wasn't even the hard part. The hardest part was left to The Clave, who had to convince the mundanes of New York that what happened was not, in fact, an apocalypse and was simply an outbreak of a horrible virus that had since been contained. But in the end, the mundanes did what they always did. Accepted the lies for truth so that they could continue living on in their blissful ignorance away from all of the chaos and unexplainable madness of the shadow world.

And Magnus and Alec also did what they always did. Held each other close and loved each other fiercely through it all. Their love a light shining through the darkness in their worlds, guiding them along their paths.

**Author's Note:**

> I was thinking about participating in kinktober, but decided I'd much rather do a horror-related fic for Malec instead. I don't see many of those. Happy Halloween!


End file.
